To test the initial model on real data, we use table 3.7 from the 2009 ICES AFWG report, with the catch for 0-2 year olds set to zero. The survey data is taken from table A.13 in the same document. (.dat-file) Population trajectories with 95% confidence intervals for the initial population size, for three cohorts starting in 1985, are given below. On the right are the contents of the file ending with .cor output by ADMB, which contains the estimates, standard deviations, and correlation matrix.

As one can see, the effective catchability is very low, due to the fact that q0 is at its lower bound of 0.05. Therefore we set the lower bound to be 0.5, (which requires editing of the .tpl file and recompilation), and then get:

This model has two q variables for each survey, one which is applied to age groups 0-2, and one which is applied to age group 3 and up. It is implemented in this .tpl file. A .pin file for three cohorts may read: